[Zope] any known bugs wrt transactions never being committed?

[Randall F. Kern]

Turns out this was a PoPy bug.

In particular, PoPy 2.0.2 has a global semaphore it blocks all queries
on, including commit and begin.

This means if you try to execute a Postgres query that has to block on
another transaction (1), you get deadlock, and a hung Zope.

-Randy

1: A common case for this is concurrent updates when run in serializable
transaction mode (the PoPy way).